A magnetic memory device (a semiconductor integrated circuit device) in which a magnetoresistive effect element is formed on a semiconductor substrate has been proposed.
The magnetoresistive effect element mentioned above has a stack structure formed of a plurality of layers including magnetic layers. The stack structure is formed by etching a stack film by using a hard mask as a mask. The hard mask is usually removed by oxidizing the hard mask. Accordingly, the performance of the magnetoresistive effect element may be adversely affected when a side surface of the stack structure is excessively oxidized in removing the hard mask.
Also, an interlayer insulating film is formed around the stack structure. Usually, the interlayer insulating film is formed in an oxidizing atmosphere. Accordingly, the side surface of the stack structure may be excessively oxidized in forming the interlayer insulating film, and the performance of the magnetoresistive effect element may be adversely affected.
Accordingly, a magnetic memory device capable of preventing the side surface of the stack structure from being excessively oxidized, and a method of manufacturing the magnetic memory device are desired.